Research On The Evolution Of Resonant Energy In The Harbor

With the continuous expansion of human resource needs, port engineering has fully developed and plays an increasingly important role in the development of the national economy. However, the complex marine environment seriously affects the safety of the port and restricts the development of the port. Because the harbors are subjected to the incidence of wind wave, swell, infragravity waves and sometimes tsunami and other factors, which may induce harbor resonance; and thus the tranquility conditions for mooring and the normal operation of the port as well as the building are threatened, which causes huge loss to the local economy. Therefore, the port resonance must be taken into account in the design and planning of the port.This thesis is structured as follows. First, a review of many harbor oscillation events happened domestically and abroad in recent decades is presented to introduce the research background and significance of the port resonance. Then the physical model tests on harbor oscillation problems by the previous scholars, the numerical models and trends on research progress are described. Second, the numerical model used in this paper, MIKE21-BW module, a model based on improved Boussinesq equations is introduced. The Boussinesq equations and numerical solution as well as the treatment of the boundary condition are described in detail. This paper simulates the waves propagating into the harbors, including long-narrow harbor, circular harbor, double circular and irregularly shaped harbor and subsequent evolution of resonance by MIKE21-BW numerical model. The incident wave frequency used here the port first characteristic frequency. As the wave surface disturbance in the harbor is a transient process, the analysis of the growing and decay process is performed with continuous wavelet spectral analysis a form of an exponential equation to estimate the time it takes for the energy to grow and decay in resonance is given.